Carbon nanotubes (CNTs), see ref. (http://en.wikipedia.org/wiki/Carbon_nanotube)
below for more information, are allotropes of carbon with
a nanostructure that can have a length-to-diameter ratio
greater than 10,00,000. These cylindrical carbon molecules
have novel properties that make them potentially useful
in many applications in nanotechnology, electronics, optics
and other fields of materials science. They exhibit extraordinary
strength and unique electrical properties, and are efficient
conductors of heat.
A simple one-step method to prepare carbon nanotubes has
been developed under the supervision of Dr. Nanda. This
method published in Nanotechnology 19 (2008) 155602 has
been featured on http://nanotechweb.org/cws/article/tech/33725.
The main feature of this method is that it does not require
a carrier gas to deliver reactants to the furnace. Hence,
it eliminates nearly the entire complex and expensive machinery
associated with chemical vapor deposition that are required
to deliver the gases in a controlled manner to the reaction
zone. The need for the tedious and time-consuming substrate
preparation is also not required.
A schematic of the simple experimental technique is shown
below. In brief a quartz tube with one end closed is loaded
with the reactants required. The quartz tube is inserted
into a horizontal tube furnace at a slight angle to the
axis of the furnace, to confine the reactants to the sealed
end. The other end of the quartz tube is connected to a
rubber bladder to collect gaseous byproducts of the reaction.
The furnace is heated up and nanotubes are formed on the
walls of the furnace. More details are provided in the publication
Schematic and photograph of the experimental setup
Quartz tube with deposition and TEM image of bamboo-like